From: Michael Vrable <mvrable@cs.ucsd.edu>
Date: Thu, 6 Dec 2007 05:25:39 +0000 (-0800)
Subject: Provide a script for converting the local database to the v0.6 format.
X-Git-Url: https://git.vrable.net/?a=commitdiff_plain;h=cae5d6103b0efeb5cd34cd67c65df745ef4d598b;p=cumulus.git

Provide a script for converting the local database to the v0.6 format.
---

diff --git a/contrib/upgrade0.6-localdb.sql b/contrib/upgrade0.6-localdb.sql
new file mode 100644
index 0000000..0733ba1
--- /dev/null
+++ b/contrib/upgrade0.6-localdb.sql
@@ -0,0 +1,52 @@
+-- SQL script for upgrading the local database to the format expected for LBS
+-- version 0.6.
+--
+-- This script should be loaded after connecting to the database to be
+-- upgraded.
+
+-- Database schema changes: the size column was added to the segments table,
+-- and the segments_used table was added.  Rather than upgrade the segments
+-- table in-place, we create a new table and then rename it over the old
+-- segments table.
+create table segments_new (
+    segmentid integer primary key,
+    segment text unique not null,
+    path text,
+    checksum text,
+    size integer
+);
+
+create table segments_used (
+    snapshotid integer not null,
+    segmentid integer not null,
+    utilization real
+);
+
+-- Compute the size of each of the segments, if possible, based on our
+-- knowledge of the objects stored in them.
+insert into segments_new
+select segmentid, segment, path, checksum, size
+from
+    (select segmentid, segment, path, checksum from segments)
+left join
+    (select segmentid, sum(size) as size from block_index group by segmentid)
+using (segmentid);
+
+drop table segments;
+alter table segments_new rename to segments;
+
+-- Populate the segments_used table based upon data contained in
+-- snapshot_contents--this is roughly the same calculation that is actually
+-- done, only now this calculation is done when a snapshot is created.
+insert into segments_used
+select snapshotid, segmentid, cast(used as real) / size as utilization
+from
+    (select snapshotid, segmentid, sum(size) as used
+     from snapshot_contents join block_index using (blockid)
+     group by snapshotid, segmentid)
+join
+    (select segmentid, size from segments)
+using (segmentid);
+
+-- The snapshot_contents table is obsolete.
+drop table snapshot_contents;